The production of metallic iron from iron ore or iron oxide can be accomplished by a variety of systems and processes. The direct reduction of iron oxide by contacting the iron oxide directly with reductant in a process known as direct reduction of iron is widely used in the industry. Direct reduction (“DR”) processes produce metals from their ores or oxides by removing associated oxygen from ores at temperatures below the melting temperature of any of the materials involved in the processes. The product obtained as a result of a direct reduction process is known as direct reduced iron (“DRI”), and is a highly metallized iron product.
Although there are many advantages to the use of DR processes for the production of metallized iron, the processes consume significant amounts of fuel, e.g. coal, natural gas, methane, or syngas, both as a source of the reducing gas and a fuel source for thermal equipment. Moreover, a significant amount of the fuel utilized is ultimately flared, with the relative amount of fuel flared dependent upon several factors, including: in part to control operating pressure of the reducing gas in DR system, production rates, and the quality of input natural gas. Flaring of fuel is not only economically inefficient, but also is environmentally undesirable as it represents a source of greenhouse gas.
Despite advances in DR production systems and processes, there remain significant inefficiencies in the use of fuel in currently available technologies. These needs and other needs are satisfied by the present invention.